$\overline{D_{\mathrm{i}}}$, $\overline{D_{\mathrm{c}}}$ and $\overline{D_{\mathrm{cc}}}$ (kpc) vs. Age (Gyr) on a logarithmic scale for a subsample of 81 open clusters (blue) at a distance < 217 pc. The clusters are also shown in 7 equally distributed bins (black colour). In the background (light gray), the our sample of ∼1500 clusters in the solar region. The black lines show the linear fit on a logarithmic scale to the clusters’ data. The most populated open clusters at a distance < 217 pc are shown in purple.